This invention relates generally to inflator devices such as for use in inflatable safety restraint installations and, more particularly, to an initiator assembly for joining an initiator to an inflator device.
Inflatable safety restraint installations typically use an inflator device to produce inflation gas for inflating the airbag in the event of a collision. The inflator device often includes a gas generant material stored within an inflator device housing and an initiator in combination with the housing that actuates the gas generant material. The initiator typically includes a reactive charge in combination with electrical connectors. A signal sent through the electrical connector actuates the reactive charge, which produces reaction products that actuate the gas generant material.
Initiators are often joined to a base of an inflator device. Initiators can also be joined to an adapter plate, and the adapter plate is joined, such as, for example, by welding and/or crimping, to the inflator device. Currently, initiators are generally joined to inflator devices or adapter plates in one of two techniques. A first technique to join an initiator to an inflator device is by inserting the initiator into an appropriate machined interface and crimping the interface to secure the initiator. Such crimping requires that a precise interface be machined into the inflator device or adapter plate. Crimping is thus relatively expensive and some crimping processes are known to have quality control problems due to burrs, e.g., metal slivers, occasionally left by the machining and/or crimping processes. The burrs can cause short circuits, for example, between the electrical connectors or one of the electrical connectors and a metal housing, or other installation problems. A second way to join an initiator to an inflator device is by integrally molding an initiator directly to an inflator device using a moldable material, such as a thermoplastic. Such integral molding is typically less expensive than the crimping method mentioned above. However, a hermetic seal between the initiator and the inflator device can be difficult to maintain as the thermoplastic expands and contracts during temperature cycles common during installation procedures. Therefore, such integral molding techniques often require carefully designed joint geometries that may not be possible in some types of inflator devices.
Thus, there remains a need for an initiator assembly that minimizes or eliminates the need for expensive and complicated machining. Further, there remains a need for an initiator assembly that provides a desirable seal with the inflator device and for an initiator assembly that is relatively inexpensive to produce and easy to join to an inflator device.